布氏菌疫苗效力评价小鼠模型的建立

Establishment of the brucellosis vaccine potency evaluation model in mice

目的建立布氏菌疫苗效力评价小鼠模型,为布氏菌疫苗有效性评价奠定基础。方法测定感染布氏菌株动物的脾脏细菌数,比较菌株毒力,筛选出布氏菌疫苗效力评价用布氏菌株。通过最小感染剂量的测定为效力评价的感染剂量提供基础数据。检测动物体内布氏菌增殖情况,确定动物解剖时间。将不同剂量的布氏菌活疫苗免疫小鼠,4周后用布氏菌强毒菌株皮下感染,感染4周后将动物解剖测定脾脏细菌数,分析疫苗保护效果。结果筛选出布氏菌疫苗效力评价感染用布氏菌株,该菌株的皮下最小感染剂量为300 CFU,感染后4周动物脾脏细菌数达到较高且稳定水平。布氏菌活疫苗免疫小鼠后能产生较好的保护效果,免疫剂量与保护力水平之间有较好的量效关系。结论建立了布氏菌疫苗效力评价小鼠模型,为新型布氏菌疫苗的研制奠定了基础。

Objective To develop and utilize appropriate animal model of Brucella infection in order to evaluate the efficacy of vaccines for human brucellosis. Methods The most virulent Brucella strain was selected by comparing the virulence. In order to establish the minimum infection dose of the selected Brucella strain in BALB/c mice, groups of 6 animals were injected with series concentration of Brucella bacteria. In order to determine the time of anatomy, mice were culled and the bacterial loads in the spleens were determined at different time after injection. Two experiments were performed to confirm and further characterize this mouse model. The mice were challenged with Brucella bacteria at 4 weeks after immunization, and the bacterial loads in the spleens were determined at 4 weeks after injection. Results The Brucella strain used for the evaluation of efficacy of brucellosis vaccine was selected, and the minimum infection dose of the selected Brucella XJ91-60 strain in BALB/c mice was 300 CFU. Bacterial loads in the spleen achieved high and stable level at 4 weeks after injection. The mice immunized with brucellosis vaccine were protected against challenge with virulent Brucella strain. Conclusion Brucellosis vaccine potency evaluation model in mice is established, which lays a foundation for the development of the new brucellosis vaccine.